Fault-indicating means for signal systems



March 17, 1942. c. POOL EI'AL FAULT INDICATING MEANS FOR SIGNAL SYSTEMS 2 Sheets-Sheet 1 Filed April 13, 1938 March 17, 1942. POOL Em 2,276,546

FAULT INDICATING MEANS FOR SIGNAL SYSTEMS Filed April 13, 1938 2 Sheets-Sheet 2 19' 8 v 1' r A {0 52 31 fin! 19 H) 1 e 50 Z3 25 j J I I/ I I 7 I 3 10 I v Z2 I f 28 I I 19 15 INVZI ;ORkS P I I BY gigigyfis gr ATTORNILIY Patented Mar. 17, 1942 FAULT-INDICATING SYS MEANS FOR SIGNAL TEMS Clark Pool, Brooklyn, and Hugo F. Cypser, New York, N. Y., assignors to Signal Engineering & Manufacturing Company, New York, N. Y., a corporation of Massachusetts Application April 13, 1938, Serial No. 201,800

7 Claims.

The present invention relates to improved means for indicating the occurrence of a fault, power failure or any abnormal circuit condition which might occur in any supervised electrical system, such, for example, as a fire alarm system, shown and described in the co-pending application of John H. Wheelock, Serial No. 74,567, filed April 15, 1936 and since issued as Patent No. 2,170,104, dated August 22, 1939.

In the aforementioned co-pending application, there is disclosed an arrangement wherein the signal for indicating trouble in a supervised electrical system is also supervised by an auxiliary signal, with provision being made for additional supervision of the auxiliary trouble indicating signal. As a result, any fault occurring in either the system under supervision, or in the always supervised trouble indicating signals, as well as failure of either the primary or auxiliary power source, is immediately called to attention by operation of one of the trouble signals.

In the normal functioning of the above described arrangement for obtaining double supervision, either trouble indicating signal is adapted to sound continuously upon the occurrence of a fault, until the fault is remedied. However, it is often undesirable to have a trouble indicating signal sounding continuously, when it may take some time to remedy a fault, and the present invention contemplates a doubly supervised arrangement, whereby a trouble signal may be silenced and a visual pilot signal substituted therefor, which pilot signal will remain energized as long as the fault exists. By this arrangement, it is possible for the person responsible for the maintenance of the associated alarm system, to silence one or the other of the trouble indicating signals while remedying the fault, without any possibility of the continued existence of the fault going unnoticed. The above and other advantageous features of the invention will hereinafter more fully appear from the following description, with reference to the accompanying drawings, in which:

Fig. 1 is a panel wiring diagram, illustrating an arrangement for obtaining double supervision, in connection with supervised pilot signals, operating in accordance with the present invention.

Fig. 2 is a panel wiring diagram, similar to Fig. 1, illustrating the functioning of a trouble indicating signal, in response to the occurrence of a fault.

Fig. 3 is a simplified schematic diagram, showing the circuits established with the system in the condition of Fig. 2.

Fig. 4 is a schematic diagram illustrating the manner of silencing one trouble indicating signal and the functioning of an associated pilot signal.

Fig. 5 is a schematic diagram illustrating functioning of the other trouble indicating signal.

Like reference characters refer to like parts in the different figures.

Referring first to Fig. 1, electrical supply mains l and 2 are normally energized from a suitable source, not shown, which is also utilized to energize the alarm system with which the supervisory arrangement of the present invention is associated. Other supply mains 3 and 4 are adapted to be energized from a source, not shown, which is separate from the source utilized to energize the mains I and 2. For convenience of designa tion, the mains l and 2 will be hereinafter referred to as the alarm system mains, while the mains 3 and 4 will be referred to as the supervisory mains.

A primary supervisory relay A comprises an energizing winding 5 having one terminal connected to the alarm supply main 2, while its other terminal is connected to one of a pair of spaced stationary contacts 6, between which a circuit is normally maintained by a supervisory bridgingcontact I. For purpose of illustration, this bridging contact 1 is indicated as being mounted on the panel of the alarm system that is to be supervisedby the arrangement of the present invention. Since this alarm system may be of any desired character, it is sufiicient for the purposes of the present description to state that the contact I will remain in engagement with the contacts 6, to bridge the gap therebetween, as long as the system remains in a normal, operative condition, with the contact 1 being separated from the contact 6, as shown in Fig. 2, upon the occurrence of a fault in the system.

The other contact 6 is connected to a stationary contact 8, forming part of a, double-pole, double-throw switch 9, having one movable arm l0 connected to one terminal of the winding II of an auxiliary trouble signal l2, assumed as being of the vibrating bell type. The other terminal of winding II is connected to the other switch arm l0 that is normally engaged with stationary switch contact 8', and a pilot light I3 is connected between the switch contact 8 and the other alarm system main l.

Therefore, in the normal condition of the system, a continuous supervisory circuit exists between the mains l and 2, which may be traced as follows: starting from the main I, the supervisory circuit includes pilot light I3, switch contact 8' and arm II), winding II of the auxiliary trouble signal I2, switch arm II! and contact 8, contacts and bridging contact I, and winding 5 of the main supervisory relay A, and terminates at the main 2. The parts. of the supervisory circuit indicated above are normally traversed by a small supervisory current, the value of which is just sufiicient to energize the winding 5 of relay A, but is not sufficient to cause operation of the auxiliary trouble signal I2, or cause illumination of the pilot light I3.

The arrangement also provides an auxiliary supervisory relay B, providing an energizing winding I4 having one terminal connected to the supervisory supply main 4, while its other terminal is connected to a stationary contact I5, forming part of a double-pole, double-throw switch I6. One movable arm I! of the switch I6 is connected to one terminal of the winding I8 of a primary trouble signal I 9, assumed as being of the vibrating bell type. The other terminal of signal winding I8 is connected to the other switch arm ll", normally engaged with stationary switch contact I5, and a pilot light is connected between the switch contact I5 and the other supervisory main 3.

Therefore, in the normal condition of the system, a second supervisory circuit exists between the supervisory mains 3 and 4', which may be traced as follows: starting from the main 3, the supervisory circuit includes pilot light 2!], switch contact I 5 and arm I I, winding I8 of the primary trouble signal I9, switch arm I! and contact I5, and winding I4 of the auxiliary supervisory relay B, and terminates at the main 4. The parts of the supervisory circuit indicated above, are normally traversed by a small supervisory current, the value of which is just sufiicient to energize the winding I 4 of relay B, but is not. suflicient to cause operation of the primary trouble signal I9, or cause illumination of. the pilot light 25.

The parts of the system described thus far, include two, independent supervisory circuits that are traversed by small supervisory currents, so that both, trouble signals I2 and I9 and pilot lights I3 and: 20 are under continuous supervision The present invention further contemplates an automatic arrangement, whereby the occurrence of any fault. in the associated alarm system, or in the. supervisory circuit, including primary relay- A, auxiliary trouble signal I2 and pilot light I3, or failure of the source supplying the system mains I and 2, will be indicated byenergization of both the primary trouble signal I9 and its pilot light 29, while a fault in, the supervisory circuit, including the auxiliary relay B, primary trouble signal I9 and pilot light 29, or failure of the source supplying supervisory mains 3 and 4,, will be indicated by operation of the auxiliary trouble signal I2, and illumination of the pilot light I3; Furthermore, thepresent arrangement provides means for silencing either trouble signal I2 or I9, without, however, extinguishing the associated pilot light I3; or 20', until the. fault which has caused energization of, either signal, or light, has been remedied; and the system restored to its normal condition.

In order to obtain the above described results, the. armature. of the primary supervisory relay A provides an arm 2I, which is maintained out of engagement: with a stationary contact 22, as-long as the relay winding 5 is traversed by supervisory current, The relay arm 2| is connected to one supervisory main I, while the contact 22 is connected to the switch contact I5, to which the pilot light 23 is also connected. Relay A also provides a movable arm 23 that is normally maintained out of engagement with a stationary contact 24, as long as the relay winding 5 is traversed by supervisory curent. This second arm 23 is connected to the other supervisory main 3, while the contact 24 is connected to the terminal of the winding I 4 of the auxiliary relay B, which is farthest removed from the supply main 4.

With the relay arm 23 in its raised position, due to the flow of supervisory current through the winding 5, this arm is maintained in engagement with a stationary contact 25 that is connected to a stationary contact 26 of the switch I5. This switch contact 25 is disengaged from the switch arm IT, in the normal position of the switch I5 shown in Fig, l, and is spaced from a contact 26' connected to the supply main 4, in common with the arm 2|, the contact 26' being normally disengaged from the other switch arm II.

The auxiliary supervisory relay B, similarly provides cooperating arms and stationary contacts 21, 28 and 29, 30, the arms 21 and 29 being connected to the system supply mains 2 and I, respectively, and the contacts 23 and 30 being connected to the switch contact 8' and one terminal of the relay winding 5, respectively, beyond the contacts 6. A third stationary contact 3|, with which the relay arm 29 is normally in engagement, is connected to a stationary contact 32 of the switch 9, with the contact 32 spaced from a contact 32 connected to the system supply main 2, in common with the relay arm 21.

Let it now be assumed that a fault has occurred in the associated alarm system that is under supervision, so that the bridging contact 'I is moved out of engagement with the contacts 6 in the supervisory circuit of the primary relay A, as indicated in Fig. 2. The resultant deenergization of the relay winding 5, immediately causes the relay arms 2| and 23 to drop back to engage the stationary contacts 22 and 24, respectively, and thereby establish a number of new circuits.

Beginning at the supervisory main 4, current flows through the engaged arm 2| and contact 22, to the contact I5 of switch I 6, at which point it divides, with a portion flowing through the pilot light 20, back to the other supervisory main 3, to cause illumination of the light. Current also flows from the switch contact I5 via the engaged arm I'I', through the main trouble signal winding I 8, and from thence to the engaged switch arm I I and contact I 5, directly to the supervisory supply main 3 through the then engaged arm 23 and contact 24 of the relay A. In other words, deenergization of the main supervisory relay winding 5, and the resulting engagement of its arms 2I and 23 with contacts 22 and 24, respectively, causes energization of both the pilot light 29 and the main trouble signal I 9, by reason of the establishment of separate circuits for these devices, from which the winding It of the auxiliary relay B is excluded. At the same time, however, the connection of the relay winding I4 across the supervisory mains 3 and 4, is maintained by reason of the fact that one terminal of the winding I4 is connected to the relay contact 24, in common with the switch contact I5.

' The above described circuits are shown in the simplified wiring diagram of Fig. 3, by the arrows.

Upon deenergization of the primary supervisory relay A, as described above, attention is called to the existence of a fault in the associated signal system under supervision, both by the sounding of the primary trouble signal I9, and the illumination of the pilot light 20. Therefore, when the person responsible for maintenance of the system approaches the panel on which the apparatus of Fig. 1 is mounted, illumination of the pilot light 20 informs him that the fault is either in the signal system under supervision, or in the devices included in the circuit of the primary supervisory relay A, or that there has been a failure of the source supplying the system mains I and 2.

Now assuming that it is desired to silence the trouble signal I9 while a fault is being located and remedied, the switch I6 is thrown to the position of Fig. 4, wherein the switch arms I! and H are in engagement with the switch contacts 26 and 26', respectively. When the switch I6 is so operated, the winding I8 of the primary trouble signal I9 is deenergized, due to the fact that the winding is no longer connected to the live switch contact I5, and that the switch contact 26 is connected to the relay contact 25 that is then disengaged from the relay arm 23. The

pilot light 20, however, remains connected across the supervisory supply mains 3 and 4, since the switch contact I5 is connected directly to the then energized relay contact 22. Therefore, the pilot light 20 remains illuminated, although the trouble signal I9 has been silenced, and the winding I4 of the auxiliary relay 5 also remains energized through the then closed contacts 23 and 24 leading to the main 3. The circuits that exist after throwing the switch I6, are shown in the simplified diagram of Fig. 4, by the arrows.

Let it now be assumed that the fault which occurred in the associated signal system is located and remedied, so that the resumption of normal conditions in the system results in returning the contact 1 into bridging engagement with the contacts 5. When this occurs, the reestablishment of the supervisory circuit through the winding 5, causes the relay arms 2| and 23 to leave the contacts 22 and 24, respectively, with the arm 23 again engaging the contact 25, as shown in Fig.

1. Disconnection of the switch contact I5 from the supervisory main 4, immediately causes the pilot light 20 to be extinguished, so as to indicate that the fault has been remedied. However, since the switch I6 is still in the position of Fig. 4, engagement of the contact 25 by the relay arm 23, causes the signal winding I8 to be connected across the supervisory mains 3 and 4, through the switch contacts 26 and 26'. Therefore, the primary trouble signal I9 again sounds, even though the fault has been remedied. Obviously, this second sounding of the trouble signal, unaccompanied by illumination of its pilot light 20, is to call attention to the fact that the switch I6 is still in the position of Fig. 4. Then, as soon as the switch I6 is thrown to the position of Fig. 1, silencing of the signal I9 indicates that the system has been restored to its normal condition of supervision.

When, as described above, correction of the fault causes the relay A to pull up to the position of Fig. 1, separation of contacts 23 and 24 breaks the holding circuit for the winding I4 of the relay B that was previously established when throwing the switch I6. Therefore, the relay B will drop out to operate the trouble signal I2 simul taneously with the signal I9 until the switch I6 is thrown to the position of Fig. 1, to reestablish the supervisory circuit of the relay winding I4 through the signal winding I8.

Upon the occurrence of any fault in the supervisory circuit, including the winding I4 of the auxiliary relay B, the winding I8 of the primary trouble signal I9 and the pilot light 20, or upon failure of the source supplying the supervisory mains 3 and 4, the resultant deenergization of Winding I4 will cause the relay arms Z1 and 29 to engage the relay contacts 28 and 3!), respectively. When this happens, the winding I I of the auxiliary trouble signal I2 and the pilot light I3, will be connected directly across the system supply mains I and 2 through separate circuits similar to those established in Fig. 2, upon deenergization of the relay winding 5. These circuits are indicated in the simplified wiring diagram of Fig. '5, from which it is evident that the auxiliary trouble signal I2 will sound coincidentally with illumination of the pilot light I3. Throwing the arms I0 and II! of the switch 9 to engage switch contacts 32 and 32, respectively, will silence the trouble signal I2, with the pilot light I3 remaining illuminated until the fault in the supervisory circuit of the auxiliary relay B has been remedied, or service restored to the supervisory mains 3 and 4, as the case may be. The auxiliary trouble signal I2 will then again sound until the switch 9 is thrown to its lefthand position, as shown in Fig. 1, thereby restoring the system to its original condition of 'double supervision.

1. Fault-indicating means for signal systems I comprising an audible signal included in a normally closed circuit, means for maintaining a flow of supervisory current through said circuit insufficient to cause operation of said signal, a second circuit including an audible signal, means for maintaining a flow of supervisory current through said second circuit insumcient to cause operation of its signal, interconnecting means for said circuits to cause operation of either signal in response to any interruption in the flow of supervisory current through either circuit, a visual signal normally included in the closed supervisory circuit of each audible signal for operation in unison therewith, and means for silencing either audible signal while maintaining energization of the associated visualsignal.

2. Fault-indicating means for signal systems comprising an audible signal included in a normally closed circuit, means for maintaining a flow of supervisory current through said circuit insuflicient to cause operation of said signal, a second circuit including an audible signal, means for maintaining a flow of supervisory current through said second circuit insuflicient to cause operation of its signal, interconnecting means for said circuits to cause operation of either signal in response to any interruption in the flow of supervisory current through either circuit, a visual signal normally included in the closed suaudible signal and a second Visual. signal in.-

cluded in the normally closed circuit,- a second source of. electrical energy for maintaining. a flow of. supervisory current throughsaid; secondnamed. signals insufficient to cause operation. thereof, interconnecting means. ior said. circuits to. cause. the simultaneous operation of. both signals. in one circuit in. response to. any interruptionrin the flow of supervisory. current through thecircuit of the other signals, anclmeans for temporarily disconnecting either audible signal fromone source or the other while maintainingthe energization of its associated visual signal. from the corresponding source.

4.. In" combination, an electrical circuit, inde--- pendent normally closed electrical. circuits, each including both. audible and visual fault-indicat-- ing means and separate. sources of electrical en.- ergy. for maintaining a flow. of supervisory current. through said circuits insufficient to cause operation. of said fault-indicating means, inter.- connecting means for said circuits, to cause. operation of both of said indicating means. for: one circuit in response to an interruption in the. flow of supervisory current in the circuit of. the other indicating means, and to additionally cause op.- eration of both indicating means for one. circuit' in response to the occurrence of a fault in the first-named circuit, and means for temporarily disconnecting either audible indicating. means from one source or the other while maintaining the energization. of the associated visualindicating means from the corresponding source.

5. Fault-indicating means for signal systems comprising a fault-indicating signal includedin a normally closed circuit, means for maintaining aflow of supervisory current through said circuit insufiicient' to cause operation of said signal, a second circuit including a fault-indicating signal, means? for maintaining; a flow of, supervisory current through said second circuit insufiicientto. cause operation of its-signal, interconnecting means for said circuitsto cause. operation. of either signal in response to any interruption. in the flow. of supervisory currentthroughs either circuit, a pilot light normally included in. the closedsupervisory circuit of each signal for operationiin unison therewith andimeans-for 1'en-' dering either signal inoperative while maintaining illumination of its pilot light.

6-. Fault-indicating means for signal systems comprising a fault-indicating, signal included in a normally closed circuit,,means for-maintaining a flowof supervisory current through said: circuitinsufiicient to cause. operation'of. said signal, a second circuit including a fault-indicating, signal, means for maintaining a flowofsupervisory current through said' second circuit insufiicient to cause. operation of its signal, interconnecting means.- for said. circuits to cause: operation ofeither signal in response to -any; interruption in the. flowof. supervisory current through either circuit, a pilot light normally included inthe closedsupervisory circuit of each signal for operationin unison therewith, means. for. rendering either signalv inoperative following energization thereof, andmeans for maintaining; illumination of either pilot light untilits associated signal isvrestored to an operative condition.

7. Fault-indicating means for signal systems comprising a. fault-indicating signal included in a normally closed circuit, means for maintaining a flow of supervisory current through said circuit insufiicientto cause operation'of said signal, asecond circuit including a fault-indicatingrsig nal, means for maintaininga flow of supervisory current through. said second. circuit insufficient to'cause operation of its. signal, interconnecting means for said circuits to. cause operation of eithersignal in response to any interruptionin the flow. of supervisory current through either circuit, a. pilotv light normally included in the closed. supervisory circuitof each signal for oper-' ation in. unison therewith, meansfor rendering either. signal inoperative following energization thereof, and. means for maintaining illumination of ether. pilot light until the flowof supervisory current is resumed inthe associated circuit.

CLARK POOL. HUGO F. CY-PSER. 

